U.S. Customs and Border Protection (CBP), apparently unable to distinguish between real guns and replicas, seized a shipment of 30 toy guns in a February bust at the Port of Tacoma in Washington. Airsoft guns, which fire little plastic balls, are used by a growing number of loyal enthusiasts (think paintball, only not as messy). In addition, thanks to their realistic look, weight, and feel, these guns are often used for training purposes by National Guard units and law enforcement. It was this realism that led CBP agents to seize the shipment—which was destined for Airsoft Outlet Northwest in Cornelius,...